Liquid fuel mixing apparatus and direct liquid feed fuel cell having the same

Abstract

Provided may be a liquid fuel mixing apparatus and a direct liquid feed fuel cell having the same. The liquid fuel mixing apparatus comprises a liquid fuel tank and a water tank, and a liquid fuel mixer that mixes a liquid fuel supplied from the liquid fuel tank and liquid supplied from water tank, the liquid fuel mixer located to contact the liquid fuel in the liquid fuel. The liquid fuel mixer comprises, a water channel through which the liquid supplied from the water tank may flow, and a liquid fuel permeable membrane, which allows the liquid fuel to penetrate therethrough to the water channel but does not allow water in the water channel to penetrate therethrough to the liquid fuel tank.

1. A direct liquid feed fuel cell, comprising:
 a membrane electrode assembly (MEA) comprising an electrolyte membrane having an anode on a first face and a cathode on a second face; 
 a first conductive plate that contacts the anode of the MEA, having flow channels to supply liquid fuel to the anode; 
 a second conductive plate to supply air the cathode; 
 a liquid fuel tank; 
 a water tank; and 
 a liquid fuel mixer located to contact the liquid fuel in the liquid fuel tank, wherein the liquid fuel mixer mixes the liquid fuel supplied from the liquid fuel tank and the liquid supplied from the water tank, and then supplies a mixture of liquid fuel and water to the flow channel, the liquid fuel mixer comprising:
 a water channel through which the liquid supplied from the water tank flows; and 
 a liquid fuel permeable membrane between the water channel and the liquid fuel in the liquid fuel tank, wherein the liquid fuel permeable membrane allows the liquid fuel to penetrate therethrough to the water channel but does not allow water in the water channel to penetrate therethrough to the liquid fuel tank. 
 
 
   
   
     2. The direct liquid feed fuel cell of  claim 1 , wherein the water channel is formed at a bottom portion of the liquid fuel tank. 
   
   
     3. The direct liquid feed fuel cell of  claim 2  further comprising a wicking member between the permeable membrane and the liquid fuel in the liquid fuel tank. 
   
   
     4. The direct liquid feed fuel cell of  claim 1 , wherein the water channel is vertically formed at an inner side of the liquid fuel tank. 
   
   
     5. The direct liquid feed fuel cell of  claim 4  further comprising a wicking member between the permeable membrane and the liquid fuel in the liquid fuel tank. 
   
   
     6. The direct liquid feed fuel cell of  claim 4  further comprising an inclination plate with a predetermined slope at the bottom portion of the liquid fuel storing area of the liquid fuel tank. 
   
   
     7. The direct liquid feed fuel cell of  claim 1 , wherein the water channel comprises a flow channel having a serpentine shape. 
   
   
     8. The direct liquid feed fuel cell of  claim 1 , wherein the liquid fuel tank and the water tank respectively include a filter for blocking the ingress of dusts and other contaminants thereinto. 
   
   
     9. The direct liquid feed fuel cell of  claim 1 , further comprising a feed pump between an outlet of the water channel and the flow channel. 
   
   
     10. The direct liquid feed fuel cell of  claim 9 , wherein the flow channel, the water tank, and the liquid fuel mixer are connected to a circulation conduit through which the liquid fuel is circulating, and air and water passed through the second conductive plate are recovered to the water tank. 
   
   
     11. A direct liquid feed fuel cell, comprising:
 a fuel cell stack having at least two membrane electrode assemblies (MEAs) , wherein each MEA comprises an electrolyte membrane having an anode on a first face and a cathode on a second face; 
 at least a conductive inter plate that contacts an anode of the adjacent MEA and contacts a cathode of a different MEA, interposed between the stack; 
 conductive end plates placed in uppermost and lowermost positions of the fuel stack contacting the facing MEAs, respectively; 
 a flow channel, formed inner face of the plates that contact each electrode, throughwhich fuel flows; 
 a plurality of fuel inlet/outlet holes, each hole forming a fuel supply or withdrawal communicating with the corresponding flow channel, perforated vertically to the plates; 
 a liquid fuel tank; 
 a water tank; and 
 a liquid fuel mixer located to contact the liquid fuel in the liquid fuel tank, wherein the liquid fuel mixer mixes the liquid fuel supplied from the liquid fuel tank and the liquid supplied from the water tank, and then supplies a mixture of liquid fuel and water to the flow channel, the liquid fuel mixer comprising:
 a water channel through which the liquid supplied from the water tank flows; and 
 a liquid fuel permeable membrane between the water channel and the liquid fuel in the liquid fuel tank, wherein the liquid fuel permeable membrane allows the liquid fuel to penetrate therethrough to the water channel but does not allow water in the water channel to penetrate therethrough to the liquid fuel tank. 
 
 
   
   
     12. The direct liquid feed fuel cell of  claim 11 , wherein the water channel is formed at a bottom portion of the liquid fuel tank. 
   
   
     13. The direct liquid feed fuel cell of  claim 12 , further comprising a wicking member between the permeable membrane and the liquid fuel in the liquid fuel tank. 
   
   
     14. The direct liquid feed fuel cell of  claim 11 , wherein the water channel is vertically formed at an inner side of the liquid fuel tank. 
   
   
     15. The direct liquid feed fuel cell of  claim 14  further comprising a wicking member between the permeable membrane and the liquid fuel in the liquid fuel tank. 
   
   
     16. The direct liquid feed fuel cell of  claim 14  further comprising an inclination plate with a predetermined slope at a bottom portion of a liquid fuel storing area of the methanol liquid fuel tank. 
   
   
     17. The direct liquid feed fuel cell of  claim 11 , wherein the water channel comprises a flow channel having a serpentine shape. 
   
   
     18. The direct liquid feed fuel cell of  claim 11 , wherein the liquid fuel tank and the water tank respectively include a filter for blocking the ingress of dusts and other contaminants thereinto. 
   
   
     19. The direct liquid feed fuel cell of  claim 11 , further comprising a feeding pump between an outlet of the water channel and the flow channel. 
   
   
     20. The direct liquid feed fuel cell of  claim 19 , wherein the flow channel, the water tank, and the liquid fuel mixer are connected to the circulation conduit through which the liquid fuel is circulating, and air and water passed through the fuel inlet/outlet hole communicating to the cathode are recovered to the water tank.